If the home button of your iPhone is broken, you might want to think again before going to a third-party repairman to get it fixed.

That's because the latest tweak to Apple's iOS 9 software renders the device useless if someone other than an Apple technician tinkers with the home button. The phone is wiped and shut down before displaying an "error 53" code.

That error came to the fore after The Guardian highlighted the matter this month. Now the law firm PCVA, based in Seattle, wants to prove that Apple is behaving illegally by knowingly disabling the devices and punishing users for not using its own, more costly repair service. It's seeking enough complaints to trigger a class action that could lead to compensation for multiple affected iPhone users.

Apple claims that the error is caused by a precaution put in place to stop the iPhone's fingerprint sensor being exploited. "We take customer security very seriously and Error 53 is the result of security checks designed to protect our customers," the company said in a statement.

That security policy underscores Apple's attitude when it comes to controlling all aspects of its products, from the software to the hardware, and even where you can go to repair your device. The company pushes customers to cover their devices through its Apple Care plan and get them fixed at its in-store Genius Bars.

The Touch ID sensor embedded in the home button is at the heart of the iPhone's security. It allows the phone's owner to unlock the device with their fingerprint as well as authenticate mobile payments, which helps explain the level of security around that component.

But customers have complained about the drastic, irreversible nature of error 53, which has caused numerous iPhone owners to effectively lose their devices and everything on them, according to complaints on Apple's support message boards.

PCVA is not only looking into seeking compensation for the broken phones themselves, but for the data -- photos, documents and apps -- lost in the process. "Our research indicates that there is no way for anyone to recover what is lost in the process," the firm wrote in a blog post.

Apple is encouraging anyone who has experienced error 53 to contact Apple Support.